William h



(No Model.)

. W. H. WRIGHT.

INSULATOR FOR ELECTRIC WIRES.

Patented May 5, 1885.

WITNESSES j 6' fiwm,

,Figure l is a longitudinal sectional elevation UNITED STATES PATENT OFFICE.

WILLIAM H. IVRIGHT, OF ROCHESTER, NEW YORK.

INSULATOR FOR ELECTRlC WHRES.

SPECIFICATION forming part of Letters Patent No. 817A'79, dated May 5, 1885.

Application filed February 2, 1885.

To all whom it may concern.-

Be it known that I, WILLIAM H. WRIGHT, of Rochester, in the county of Monroe and State of New York, have invented certain new and useful Improvements on Telegraph-VVire Insulators; and I do hereby declare that the following description of my said invention, taken in connection with the accompanying sheet of drawings, forms a full, clear, and exact specification, which will enable others skilled. in the art to which it appertains to make and use the same.

My present invention has general reference to improvements in telegraph-wire insulators and it consists, essentially, in the novel and peculiar combination of parts and details of construction, as hereinafter first fully described, and then pointed out in the claim.

In the drawings already mentioned, which serve to illustrate my said invention more fully,

through an insulator constructed in accord with my invention. Fig. 2 is a transverse sectional plan in line a; 00 of Fig. 1.

Like parts are designated by corresponding letters of reference in both figures.

The object of my invention is the production of a simple and efficient telegraph-wire insulator. To attain this end I construct the same, A, of the usual external contourthat is to say, with a neck or groove, a, for the reception of the wire, and a downwardly-extending apron, said insulator being made of glass, molded and cast in the usual manner, and provided internally with a serewthread, E, by means of which it is secured upon the peg or pin B.

In glass insulators the apron forms thelower portion; but in those now in most extensive use said apron is of a largerinternal diameter than the size of the peg. This construction,

though desirable,is objectionable for the reason that the groove a is in a position so near to the lower portion of the screw-thread as to but imperfectly support the insulator upon the peg.

(No model.)

To avoid this objection, and at the same time give additional support to the insulator and retain the advantages of the apron, I provide my insulator with a corrugated portion,- O, extending from the lower edge of the insulator to within a short distance of the screw-threaded portion, said corrugated part being arranged to fit the peg B with its points D only. By thus giving to the or a portion of the interior of the insulator the corrugated contourl derive the advantages that, first, the bearing upon the peak is extended downwardly to the full depth of the apron; second, that the projecting points D lock upon the peg B nearly as soon as the insulator is screwed upon the peg by the wood swelling an d entering the corrugated portion, while at the same time air is admitted to the peg to prevent rotting of the wood.

It will therefore be readily seen that this corrugated portion of the interior of my improved insulator performs a very important function, and this notwithstanding the fact that the cost of manufacture has not been increased thereby in any way.

Having thus fully described my invention. I claim as new and desire to secure to me by Letters Patent of the United States As an improved article of manufacture, a telegraph-wire insulator having in its interior a screw-threaded portion, substantially as described, and a corrugated portion, 0, as stated, the corrugations running vertieallythat is to say, in line with the center line of the threaded portion, substantially as specified-said insulator being adapted for application upon a screw-threaded peg, B, having the enlarged portion 1), as and for the object stated.

In testimony that I claim the foregoing as my invention 1 have hereto set my hand in the presence of two subscribing witnesses.

WILLIAM H. WRIGHT. Attest:

FRITZ Voons, HENRY W. Luce. 

